Prior to the conception and development of the present invention, hoof thrush in horses and other hoofed animals has been treated mostly with liquid treatments. Thrush is a very common bacterial or fungal infection that occurs on the hoof of a horse or similar animal. Chlorhexidine ointments in a hydrophilic base are well know for topically treating surface wounds in animals. Commercially available ointments going by the names of Nolvosan® and Vetasan™ ointment are examples of antimicrobials for use with animals and containing chlorhexidine. However, for thrush on horse hooves, these lack the efficacy of the present invention. Also, many of the current treatments are messy to use and cause staining.
In addition, the applicant is unaware of copper sulfate, especially in the relatively high concentrations of the present invention, being a major component in any disclosed treatments of this nature. Ointments or pastes with chlorhexidine in a hydrophobic base such as petrolatum are not known to be available. In U.S. Pat. No. 5,780,064, Meisters et al. discuss various hoof diseases and treatments thereof. Use of copper salts is discussed, but with an upper limit of 20 percent by weight for copper sulfate (Col. 3, line 33). Meisters' disclosed invention is for an aqueous composition comprising copper salt, a quaternary ammonium compound, and a peroxide; and, it is intended primarily for footbaths.
US Patent Published Application 2005/0271595 discloses a long list of antimicrobial agents, of which chlorhexidine is one, and also includes a very long list of emollients, including petrolatum, which can be incorporated into an alcohol/water gel, which is the main ingredient of the prior art disclosure. However, none of the specific examples include even these two components together.
US Patent Application Publication 2010/0234460 discloses treatments of hoof diseases that offer greater resistance to contact with manure. One embodiment incorporates chlorhexidine salts, but in combination with carboxylic acids and surfactants.
U.S. Pat. No. 6,716,441 discloses skin care compositions combining a skin care active with a hydrophobic barrier protectant. It has been known to use copper sulfate as an antifungal in some treatment compositions, but not in combination with the other two components of the present invention. Before now, it has not been known to include copper sulfate in the concentration range of the present invention for any medical treatment.